An intercomparison of relative spectral responsivity measurements of illuminance meters was carried out among five companies-TOPCON, HIOKI, Minolta Co., Ltd., Yokogawa M&C Corp. and Matushita Electric Industrial Co., Ltd.
The spectral responsivity of the illuminance meters were measured by each company's spectral responsivity measurement system calibrated to each company's standard. As a result, the measured values of fs (fs is error definition of relative spectral responsivity recommended by Japanese Industrial Standard JIS-C-1609) were different within 1.7. The fs is identical with f1' recommended by CIE.
